Table 3. Photophysical parameters of C8-aryl-dG modified NarI(12).
| X | N | λex | Δλex | λem | Δλem | Δν | Irel |
|---|---|---|---|---|---|---|---|
| (nm)a | (nm)b | (nm) | (nm) | (cm−1)c | (em)d | ||
| FurG | /e | 312 | / | 381 | / | 5804 | / |
| FurG | C | 314 | 2 | 381 | 0 | 5600 | 0.45 |
| FurG | G | 312 | 0 | 382 | 1 | 5873 | 0.48 |
| FurG | THF | 305 | -7 | 383 | 2 | 6677 | 2.21 |
| FurG | −2 | 306 | -6 | 380 | -1 | 6364 | 2.97 |
| PhG | / | 290 | / | 395 | / | 9166 | / |
| PhG | C | 302 | 12 | 394 | -1 | 7732 | 0.38 |
| PhG | G | 300 | 10 | 391 | -4 | 7758 | 0.28 |
| PhG | THF | 297 | 7 | 398 | 3 | 8544 | 0.79 |
| PhG | −2 | 296 | 6 | 395 | 0 | 8467 | 0.80 |
| CNPhG | / | 334 | / | 464 | / | 8388 | / |
| CNPhG | C | 332 | -2 | 462 | -2 | 8476 | 1.04 |
| CNPhG | G | 335 | 1 | 462 | -2 | 8206 | 2.28 |
| CNPhG | THF | 335 | 1 | 453 | -11 | 7776 | 2.00 |
| CNPhG | −2 | 333 | -1 | 457 | -7 | 8148 | 3.92 |
| QG | / | 321 | / | 477 | / | 10 189 | / |
| QG | C | 322 | 1 | 475 | -2 | 10 003 | 0.41 |
| QG | G | 324 | 3 | 480 | 3 | 10 031 | 1.55 |
| QG | THF | 327 | 6 | 467 | -10 | 9168 | 2.24 |
| QG | −2 | 329 | 8 | 468 | -9 | 9027 | 4.92 |
aAll spectra of single-strand NarI(12) and duplexes (6 μM) were recorded in 50 mM sodium phosphate buffer, pH 7, with 0.1 M NaCl at 10ºC.
bChange in excitation or emission maximum for duplex versus single strand.
cStokes’ shift (Δν) is calculated as (1/λex – 1/λem).
dIrel = Iduplex/Isingle-strand
e/ indicates optical properties of the modified base in the single strand.